president's address. 225 



days, but exhibit no genealogies of developments. Till they 

 do this, I should certainly feel hesitation ere I accepted the 

 doctrine of Mr. Darwin and Topsy, and " speck'd I was not made, 

 but growed." 



Mr. Darwin has escaped much criticism by declining to have 

 anything to do with the origin of the primary mental powers, 

 any more than with that of life itself; and there is only one 

 allusion to the antiquity of man, in which he remarks that Mr. 

 Horner's researches have rendered it in some degree probable that 

 man, sufficiently civilized to have manufactured pottery, existed 

 in the valley of the Nile 13,000 or 14,000 years ago. It is an 

 unfortunate remark, to say the least, as Mr. Horner's discovery 

 was upset by the discovery of a Roman tile below his much 

 vaunted pottery. Even supposing Mr. Horner's theory had not 

 received this cruel blow, it might have been enough to observe, 

 that he omitted two points in his calculations; 1st, That when 

 the delta was further up the country, the deposit there would be 

 annually thicker than at present; and, 2nd, That a piece of 

 pottery would naturally work down in soft water-permeated 

 sediment below the surface on which it was first cast forth. 



His strongest argument for hereditary descent seems to me to 

 be the fact of the succession of the same types in the same 

 areas during the Tertiary period. Here geology supplies the 

 evidence. And we must explain it, either by the theory of 

 generation in one spot, with subsequent migration, or by that of 

 Agassiz — different centres of creation. It is presumptuous to 

 pretend to decide ; but, for my own part, the doctrine of Agassiz, 

 with some modification, does seem to me the most reasonable. 

 By modification, I mean that to assume simultaneous creation, or 

 the repetition of the creation of forms of birds, e.g.^ and plants, 

 which could migrate to separate regions, and are almost, or 

 altogether identical, is unnecessary. Nor need we accept the 

 doctrine of the immutability of species, against the evidence 

 that species do vary under artificial selection, and therefore 

 might, and probably would do so under the process of natural 

 selection. It seems, in the present state of science, impossi ble to 

 treat either doctrine as proved or provable. 



